Authors

Abstract

An experimental habitat management program was initiated to improve the carrying capacity for northern bobwhites ( Colinus virginianus) on private lands by the Wisconsin Department of Natural Resources (WDNR) in 1974. During 1975-80, extensive habitat restoration was undertaken on a 60-mi2 (l55-km 2) study area in Richland County to restore hedge row cover, improve riparian corridors and woodlot edges, and construct plots of food and shelter to function as wintering sites for bobwhites. Previous investigations in Wisconsin have documented that the long-term decline of bobwhites was the result of habitat deterioration, principally hedgerow cover. Elsewhere, continuous declines in bobwhite abundance suggest a re-evaluation of the validity of time-honored habitat management practices is in order. Therefore, it seemed appropriate to test the impact of extensive attempts at habitat restoration, especially the development of hedgerows, on one small treatment area in the northern fringe of the geographic range of the northern bobwhite. After 10-15 years of growth, only 25% of the planted hedges were found to be effective for wintering bobwhites (i.e., closed canopies and producing fruits). Planted hedgerow cover suffered from poor survival due to deer browsing, competition from other surrounding vegetation, and changes in property owners and attitudes as farms were sold. Linear brushy cover was measured in 1990 and compared to similar estimates from 1978. During the 12-year span, brushy linear cover, including project hedges, decreased by 41% (5,995 to 3,545 yards/square mile; 2,531 to 1,497 meters/square kilometer). In addition, managed winter food resources after 1980 were reduced by half compared to earlier efforts. Through 1991, bobwhite population trends on the treatment area did not differ from statewide trends, indicating that extensive habitat restoration work had no discernible impact with respect to reversing population declines. Over 60% of the annual variability in bobwhite abundance in Richland County is related to the severity of winters. Despite these results, we still cannot discount the value of managing for hedgerows in Wisconsin. Achievements of this project include: (I) developing a bobwhite management strategy on a landscape scale, (2) gaining a high level of landowner cooperation, and (3) implementing an extensive amount of habitat restoration on private agricultural lands at minimal costs. The major problem with our overall approach is that such habitat restoration work requires continuous attention and maintenance over time to maintain effectiveness. Landowners, while highly cooperative, are not interested in protecting or maintaining habitat improvements for wildlife unless they have a vested stake in the project (i.e., a sense of "ownership"). Habitat restoration on private agricultural lands necessitates first working to change landowner attitudes towards wildlife, with the development of private lands habitat programs as a secondary concern. The outlook for northern bobwhites in the northern fringe of their range is not bright. Northern bobwhite populations will not recover unless they become a by-product of the contemporary agricultural landscape. Unfortunately, this is not the case in Wisconsin and it is unlikely to change in the foreseeable future.